Over the past 48 hours, there has been a spike in complaints around Google AdSense showing huge CPC, cost per click, declines after August 5th...

...Many are saying they are seeing a 50 to 70% drop in their cost per clicks they are getting on the ads on their web sites....

...Google has confirmed the issue. Note, your CPCs will not change, it was not a reporting glitch. It does seem to be an issue with how some rouge advertisers were able to maybe game the system. So going forward, Google blacklisted these advertisers and hopefully closed this loophole they discovered. Here is Google's statement:

Quote:

Over the past 48 hours, a number of AdSense publishers alerted us to an issue with declining cost-per-click for ads on their sites. We were able to identify the cause of the issue quickly and resolve it quickly: Several ad buyers were using irresponsible campaign parameters, lowering query coverage for specific creative types in some countries. The ad buyers responsible have been blacklisted and impacted publishers should see that their coverage is back to normal in their AdSense account.